Alkylation



invention,

Patented May 8, 1945 ALKYLATION,

Carleton Ellis, deceased, late. ofMontclair, N. J., by Carleton Ellis, Jr., and Bertram Ellis, both of Washington, D. 0., and Bank Montclair, N. J., executors;

of Montclair, said Carleton Ellis assignor to Standard Oil Development Company, a corporation of Delaware N Drawing. Original at Serial No. 345,854. D

tion July 11, 1942, Serial pplication July 16, 1940, ivided and this applica- I 9 Claims. (Cl. Mill-683.4)

This application is a division of copending application Serial No.345,854, filed July 16, 1940. This invention relates to alkylation products and process of making same, and relates especia1- ly to the formation of isoparaffins from anopen 1 chain olefin hydrocarbon and a tertiary hydroe carbon saturate. It also involves the interaction of such unsaturated and saturated hydrocarbons in the presence of activating sulfuric acid containing an alklation-promoting agent.

Interaction of olefinic hydrocarbons and tertiary hydrocarbon saturates in the presence of :activating sulfuric acid is inhibited by a num-.

ber of substances. These inhibitors include compounds of members of group VA of the periodic table, e. g., arsenic compounds, and also members of group IIIA of the periodic table, such as aluminum or compounds of boron. There- .fore, it is preferred to use sulfuric acid which is substantially free from compounds such as those mentioned above. Also, it is preferred to carry out alkylation operations in vesselsjwhich are made of materials substantially devoid of inhibiting substances. Apparently the inhibiting action of the above named substances, upon a1- kylation operations, is observed whether the activator poison is present in its elemental form,

as, for example, aluminum, or in a compound,

such as boric acid.

.Alkyl sulfates, both the acid derivative and those of a dibasic character, for example, diisopropyl sulfate, likewise tend to retard or repress the alkylation reaction. The organic sulfates which exhibit an inhibiting effect on alkylation are those in which the hydrocarbon chain is relatively short, as for example, of the order of 3, 4, 5 car bon atoms or. thereabout. Alkyl hydrogen $111- fates and dialkyl sulfates may be formed during the alkylationstep by union of sulfuric acid with the olefin hydrocarbon charging stock. However, the inhibiting effect of such sulfate compounds is overcome apparently to a substantial degree, according to the invention, by certain agents which promote the alkylation reaction, i. e., combination of olefin and paraffin. It

is not wished to infer that the alkylation-promoting agents-herein disclosed completely suppress formationof alkyl hydrogen sulfates and dialkyl sulfates. On the other-hand, it is found that certain agents promote the alkylation reaction, thereby overcoming to marked extent the inhibiting effect of the alkyl hydrogen sulfates and dialkyl sulfates.

Alkylation-promoting agents, according to the the periodic table, e. g., sulfur, selenium, or tellurium. These elements may be employed individually as promotorial agents for alkylation of I tertiary hydrocarbon saturates with open chain olefins in the presence of activating sulfuric acid. I

On the other hand, two or more Of the promotorial agents, if desired, may be employed simultaneously or in any manner, suitable to the particular set .of reactants, temperature, pressure, and other variables. Other alkylation-promoting agents suitable for the purpose comprise halides of the, metals of groupsHB and IIIA of the periodic table, as, for example, aluminum chloride. Further, it has been observed that wetting, emulsifying and frothing agents act as promoters or accelerating agents for alkylation of saturated hydrocarbons containing tertiary carbon atoms with open chain olefinic hydrocarbons in the presence of activating sulfuric acid. Examples of such promoting agents include the salts of condensation products of hydroxy or halogenated ethanesulfonic acids with amides, or

substituted amides of fatty acids or the salts of amides or substituted amides of fatty acids alonev Another type of wetting agent which' may be used as alkylation-promoting agent according to theinvention is a salt of the sulfuric acid ester of aliphatic alcohols, such-as sodium lauryl sulfate. Instead of sodium lauryl sulfate, other salts of alkyl sulfates may be used. Also,,if desired, a

combination of saltsof various alkyl sulfates may be utilized as alkylation-promoting agents. The alkyl group of the wetting agent described above may be either saturated or unsaturated. Fur- 1 ther, the hydrocarbon chain of the salts of alkyl include the elements of group VIA of sulfates preferably contains about 10 to 14 car- A bon atoms, or thereabouts.

It was pointed out previously that alkyl sulfates and alkyl acid sulfates in which the hydro- I carbon chains were of the order of 3, 4, or 5 carbon atoms, or thereabouts, exhibited an inhibit:- ing effect on alkylation of tertiary hydrocarbon saturates with olefins in the presence of activating sulfuric acid. However, it has been observed that alkyl sulfates containing, say, 10, 12, or 14 carbon atoms per molecule not only failed to eX- hibit an inhibiting effect, buton the other hand, acted as alkylation-promoting agents'for the purpose. In other words, high molecular weight esters of sulfuric acid appear to exhibit an effect (i. e., promoting) which is just the reverse of that (i. e., inhibiting) shownby low molecular weight esters of the same type.

Olefinic hydrocarbons such as isobutylene, di-

isobutylene, tetraisobutylene, and thelike, interact with saturated aliphatic hydrocarbons which contain a tertiary carbon atom of which isobutane and isopentane are examples, in the presence of activating sulfuric acid containing an alkylation-promoting agent. Or, if desired, the olefinic reactant may be a straight chain cornpound. To illustrate, n-butylene (n-butene) or n-hexylene (n-hexene) may be employed in place of the isoolefins such as those mentioned above. Intimate contact of the hydrocarbon reactants with each other and with the activating sulfuric acid containing an alkylation-promoting agent aids both the completeness and degree of alkylation. Preferably, therefore, the reactants are kept in the liquid phase. This may be effected by lowering the temperature of reaction or by increasing the pressure, or both. In this way hydrocarbon reactants which are gases at atmospheric temperatures and pressures, e. g., isobutane, n-butylene, isobutylene and the like, may be maintained in the liquid phase while in. contact with the activating sulfuric acid containing an alkylation-promoting agent and with each other. However, it is not necessary to maintain allreactants in the liquid phase. In some cases it may be desired to conduct alkylationoperations with one hydrocarbon component in the liquid phase, and the other hydrocarbon component in the vapor phase. For example, a saturated hydrocarbon containing a tertiary carbon atom may be agitated with sulfuric acid containing an alkylation-promoting agent at a temperature and prcssureat which the hydrocarbon will remain substantially in the liquid state. The gaseo'us olefinhydrocarbon then may be conducted in aslow stream through th mixture of activating sulfuric acid containing an alkylation-promoting agent and tertiary hydrocarbon saturate. Also, both tertiary hydrocarbon saturate and olefin may be maintained in the gaseous phase during alkylation. As an alternative procedure, the two reactants may be admixed in the gaseous phase and allowed to stream through an alkylation agent such as activating sulfuric acid containing an alkyla'tion-promot'ing agent.

Again, a mixture of olefins, such as one containing propylene and butylene, may be an appropriate alkiyla-ti'ng agent. Similarly, a mixture of two or more tertiary hydrocarbon saturates, e. g., isobutane and isopentane, may be employed if desired.

Instead of using the olefin inits monomeric form, it's'dimer'ic or trimerio isomer may be employed; The latter many'times appear to give as good results as the monomer and being liquids at ordinary temperatures, are much easier to hair dle. Thus diisobutylene or triisobutylene oftentimes is a more convenient alkylating agent than iso'butylene. Furthermore, the dimer or trimer seems to react, at least to a very substantial degree, in the presence of sulfuric acid containing an alkylation promoting agent as if it were the monomer. Thus, diisobutylene and isobutane interact to furnish a very considerable yield of isoocta'n'e's and not mainly dodecanes as might be expected. In like manner, instead of using a mixture of olefmic hydrocarbons, e. g., propylene admixedwith butylene, the co-polymer resulting from the interaction of such olefins may be employecl.

The following mode of procedure indica tEE t Fe general character of the alkylation operation. In

each experiment 920 g. of sulfuric acid of 98%v strength were placed in a reaction flask together sults included in Table I below indicate there pressing or inhibiting action of these agents both with the substances being tested as accelerating or repressing agents, and the whole mixture cooled to about -l5 C. Liquid isobutane amounting to 460 g. was added to the mixture and the composition stirred for a few minutes. Then 92 parts of diisobutylene having a boiling range from 102-l05 C. were incorporated dropwise with vigorous agitation over a period of about minutes. During the addition of the olefin the tem- -perature of the bath surrounding the reaction The hydrocarbon layer was washed with water,

yield of octane stock, ome emphasis is placed.

upon the production of this material. Alk'ylationinhibiting substances include arseniousj acid, boric acid, aluminum, and diisopropyl sulfate. .The're' on the total yield of reaction products and on the yield of o'ctane's.

Table I Inhibitin a cut Blank Amni- -Bfic Alum I E i g g ous acid, acid num g g gf Per cent by wt. of

added compound. 0.5 10 1 0. 5 Total yield of reactionproducts I grams 136. 2 118. 2 90.1 115.5 105.4 Fraction boiling up to 100 C. grams 21.5 17.3 6.6, 15.1 1214 Fraction boiling 1 from 100-130 C.

grams... 56. 3 45. 7 19. 2 4150 31. ('v Fraction boiling from -175 C. 1

, grams 25. 7 12. 8 12. 8 20V 4 10. 8 Fraction boiling above C. 1

, grams" 32. 7 42. 4 51.9 39. 0 150. 6 Yield of octane stock per 091117.; 30 24; 4 10.2 22 1G. 0

It will be noted from a comparison ofthe total yields of reaction products that addition of any of the inhibiting agents disclosed above caused a decrease in the total yield of reaction product as compared with that secured when only 98% sulfuric acid (column 1) was used as activating agent. Further, it will be seen that the presence of the inhibiting agents also-causes ad'ecrea's'e in the yield of octane stock. i

Using the procedure described above for lation, a number-of substances were found to have alkylation-promoting properties yhen added to the activating sulfuric acid. Thes'e alkylation-promoti'ng agents included selenium, sulfur, aluminum chloride, sodium salts titan densation products ofhydroxy or halogenated ethane sulfonic acids: with the salts of substi acid or its compounds. it is formed in the presence of substantially tuted amides of fatty acids, as, 'for example, the material designated as Igepon T, I 1

and sodium salts of sulfuric acidflesters of high molecular weight aliphatic alcohols, such as the product knownas Gardinol, sulfated lauryl alcohol. The results included in Table II belowindicate the alkylation-promoting action ofthe tion of .thiselement was present in the product.-

As a consequence, distillation of-the hydrocarbon material (resulting from the interaction of,

say, diisobutylene and isobutane) may yieldsome fractions particularly those of the higher boiling agents described above, both on the total yield 111 rangea containing sulfur and/or its derivatives, of reaction products and on the yield of octanes. e. g., hyclrogen sulfide or mercaptans.

Table II Alkylation-promoting agent Blanlc- Selenium Sulfur l g Igepon '1 Gardinol 4 Percent by wt. of added compound... t l 2 7 0.2 1 Total yield ofreaction products.grams 136.2 140. 7 145.1 127.9 130.9 123.8 Fraction boiling up to 100 C. ...d 21. 5 27. 5' 32. 1 28. 9 24. 9 7

Fraction boiling from 100-130 C.do 56.3 07.83 62.6 63.2 63. 7 1 60.1

Fraction boiling from 130-175" C.d 25. 7 18.5 23.0 13.6 l7. 13.3

Fraction boiling above 175 C; do 32.7 28. 2 T 26. 5 22.2 24, 8 21.7 Yield. of octane stock -.per cent... 30 36 33.2 H 34 34 32 Other temperatures than those mentioned in theabove described general proceduremay be employed in interacting open chain olefins with tertiary hydrocarbon saturates by means-cf activating. sulfuric acid containing an alliylationpromoting agent. Thus, for example, in Table III are indicated results secured using the above described general procedure, except that the temperatures of alkylation were and C. t

Table III and Table III, it will be noted that addition of alkylation-promotingagents to the sulfuric acid substantially increases the yields of octanes. Furthena comparison of Table II and Table III with Table I clearly indicates the greatly increased yields of octanes secured with the aid of alkylation-promoting agents over those obtained when alkylation-inhibiting agents are present.

The alkylation process involved herein co1ncomprising essentially the interaction of a butene and isobutane in the presence of activating sulfuric acid containing an alkylation-promoting agent.

This condition, 1. e., presence of sulfur or its 3 derivatives, may be eliminated or at least to a of solid alkali or alkaline-earth sulfide whereby extraction of elemental sulfur may be accomplished. Still another procedure includes distillation of the entire product, or a portion thereof, say, the octane fraction and higher, under reduced pressure.

Alkylation-promoting agents suitable for my I purpose, however, are not and should not be limited to those specifically described in the examples hereinbefore given. In addition to the sub- '1 stances mentioned, tellurium may be used as alkylation-promoting agent, as well as salts of a sulfonated or sulfated aliphatic hydrocarbon.

Alkylation-promoting agent Blank Sulfur Blank Sulfur Per cent by wt. of added compound 2 2 Temperature of reaction, O. -25 -25 -30 30 Total yield of reaction products I g'laIrlS.v 135. 9 119. 3 122. 0 105. 6 Fraction boiling up to 100 C. t

' grams 29.0 V 22. 2 22. 2 16.8 Fraction boiling from 100 to 130C. grams 43. 9 49.9 t 37.2 40. 9 Fraction boiling from 130 to 175O. i grains 20. 4 11. 0 20. 5 1 1. 7 Fraction boiling above 175 C. grams. 42. 6 36.2 42. 1 36. 2 Yield of octane stock. per cent 23 27 20 22 From an inspection of the data 111 Table II The latter may be saturated or unsaturated, and

maycontain elements other than carbon and hydrogen in th aliphatic chain, as, for example, oxygen, nitrogen or sulfur. Any one of the latter elements or any one pair or all of. them may be R present in the aliphatic chain, Also, any combination of two or more of the alkylation-promoting agents disclosed herein may be employed.

It is, of course, in the light of the present disclosure, now feasible tomak various modifications in the alkylation operation which has been i illustrated and described above. Although the reaction as described is brought about at atmos- .pheric pressure, it is quite possible to use higher mixture to a warm or even a hot condition, where- I present.

In some cases the product is characterized by or lower pressures. When the higher pressure is used, a pressure vessel may be employed which; permits raising of the temperature from that below 0 C., as illustrated here, to as high as 50 or 60 C., or higher, and thus bring the reacting upon interaction takes place even more readily when activator-poisoning substances are not or even a hot condition, interaction takes place even more readily when an alkylation-promoting agent is present.

Since the materials in question do not act at Also, when the reactants are in a worm higher temperatures, suchas 70 0., the tempera tur'e at. which ordinary alkylation is frequently carried out, it is possible that there may be a critical temperature at which the promotion agents involved are active. This shouldlie somewhere between 70 C. and cold room temperature.

Reference in the specification to the various groups of the. periodic table refers to the Mendelyeev Periodic Table; particularly with respect to the A and B designations, they are in accordbon containing at least one tertiary hydrocarbon I.

per molecule under alkylation reactioncondi-tions at a. temperature below 70 C. but above the solidification point of the reaction mixture in the presence of concentrated sulfuric acid of alkylating strength and containing as the sole ingredient 1.!

admixed therewith an element of group VIA of the periodic system. 2. A process as in claim 1 wherein. the paraffin is isobutane and the olefin a normally gaseous monoolefin.

3. A- process as in claim 1 wherein the element in admixture with sulfuric acid is sulphur.

4-A process which comprises reacting isoparaflin with monoolefin under alkylaticn reaction conditions in the presence of sulfuric acid of 90-100% strength and containing as the sole ingredient admixed therewith promotional amounts of sulfur.

' 5. A process which comprises reacting isobutane with at least one C4 monoolefin under cold room temperatures'in the presence of concentrated sulfuric/acid of alkylating strength, said acid containing as the sole ingredient admixed therewith promotional amounts of an element of group VIA of, the periodic system.

6. A process as in claim 5 wherein the added element is sulphur.

7. A process as in claim 5 wherein the added element is selenium. v 8. A process which comprises reacting isobu tanewith diisobutylene with agitation at between about l4 and aboutl6 C. in the presenceof sulfuric acid of about 98% concentration, said .acid containing as the sole ingredient admixed therewith promotional amounts of elemental sulfur.

9. Aprocess as in claim 8 wherein the amount about 2% by weight. w CARLEFION ELLIS, Ja, BERTRAM ELLIS, BANK OF MONTCLAIR; By F. JUSTIN WEBER;

' I Trust Officer, Executors of the Estate of Carleton Ellis, De-

ceased. i

of elemental sulfur is 

